New Insights into the Risk of Heart Attack in Stroke Patients

In stroke patients, the so-called troponin marker helps to assess the risk of an associated heart attack. This is a result of a joint study by DZNE and the German Center for Cardiovascular Research (DZHK), both of which are members of the German Centers for Health Research. The findings could pave the way for better treatment.

Patients with acute stroke often also suffer heart complications. In individual cases, however, it is difficult to assess whether stress-mediated heart damage is present or an acute heart attack, i.e. a circulatory disorder of the heart muscle that needs to be treated as quickly as possible. Determining the troponin level in the blood helps with the medical decision. This checks for a protein that comes from the heart muscle cells. If its concentration is very high, this indicates a heart attack – and then cardiac catheterisation (coronary angiography) is required. If then a vascular occlusion or a critical narrowing is detected, a “stent” can be inserted: This implant is used to widen the vessels and improve the heart’s blood supply.

Heart attacks more common than expected

In everyday clinical practice, cardiac catheterisation is currently only performed in around one to two percent of stroke patients. This could change thanks to an interdisciplinary research collaboration between cardiologists and neurologists. The joint PRAISE study by DZHK and DZNE – in which around 250 adults with acute stroke and highly elevated troponin levels were examined – revealed that half of all patients actually also had a heart attack.

“This is a surprisingly high proportion, at least from a neurologist’s point of view; we had not expected so many heart attacks,” says Prof. Matthias Endres, Director of the Department of Neurology with Experimental Neurology at Charité - Universitätsmedizin Berlin and researcher at DZNE’s Berlin site. He led the study together with his colleagues Prof. Christian Nolte and Prof. Ulf Landmesser from the Deutsches Herzzentrum der Charité.

According to the study, around 20 per cent of stroke patients were affected by a type 1 heart attack, which should be treated immediately. A further 30 per cent of patients were diagnosed with a type 2 heart attack, which is triggered by a lack of oxygen in the heart, but in which no blood clots or vascular constrictions form.

Troponin threshold value can help with the therapy decision

In addition, the PRAISE study found that a more than five-fold increase in troponin levels indicated a high probability of a type 1 heart attack. “This is a relevant finding,” says Nolte. “The new threshold value can help to decide which patients with a stroke should undergo coronary angiography.” If there is a vascular occlusion or a critical narrowing of the coronary arteries, a stent can be applied. The hope is that this will improve the prognosis for patients and reduce their mortality rate.

Treatment study planned

The study was a first step in this direction. “PRAISE is a diagnostic study to better understand the mechanism of heart damage,” emphasises Endres. “Next, we want to conduct a treatment study to investigate whether we can improve the prognosis of stroke patients with fivefold elevated troponin levels with the help of a cardiac catheter and the appropriate treatment.” Only then will it be possible to make binding recommendations for clinical practice.

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